Ag Line: Winter Weed Control
By Wade Parker County Extension Coordinator

Winter weeds might be out of sight and out of mind, but now is the time to think about applying pre-emergent herbicides to lawns. Yes, it is actually getting on the late side for an application but it is not too late. We have had some unusually warm weather for this time of year, which has delayed the germination of winter weeds. However, the weather will eventually change and cold weather will be upon us.

What winter weeds will I control?

There are several species of winter weeds that one can control with a pre-emergent application of atrazine + pendimethalin. A pre-emerge application of atrazine at 1oz/ 1,000 sq. ft will control many broadleaf weeds including annual bluegrass, Florida Betony, dichondra, chickweed, and suppress dandelions and wild garlic. These are the most common winter weeds homeowners have to deal with. Atrazine will still control annual bluegrass and chickweed once it has emerged. However, the addition of 2, 4- D will be needed to control wild garlic and dandelions. The addition of pendimethalin will help suppress crabgrass germination in the spring.

Homeowners need to water lawns immediately or, at least, within a day or two of application of the herbicide. A soaking half-inch of water is necessary to move the herbicide into the soil germination zone. During a mild winter with rain, it may be necessary to apply the herbicide a second time in early January.

The treatments described above can be performed on Bermuda, St. Augustine, and Centipede. Once Bermuda grass begins to break winter dormancy, it is very important not to use atrazine. In other words, atrazine does not need to be applied in the spring or summer. As for now and in the winter, it will be fine to use atrazine on Bermuda.

Always remember, the best method of lawn weed control is to perform cultural practices to maintain a healthy lawn through the fall and winter. The practices include regular mowing, irrigation, and fertilization!

The University of Georgia Cooperative Extension offers educational programs, assistance and materials to all people without regard to race, color, national origin, age, sex or disability.